A sintered body with a composition consisting of 25% to 35% by weight of R
(wherein R represents one or more rare earth elements, providing that the
rare earth elements include Y), 0.5% to 4.5% by weight of B, 0.02% to
0.6% by weight of Al and/or Cu, 0.03% to 0.25% by weight of Zr, 4% or
less by weight (excluding 0) of Co, and the balance substantially being
Fe, wherein a coefficient of variation (CV) showing the dispersion of Zr
is 130 or lower. This sintered body enables to inhibit the grain growth,
while keeping the decrease of magnetic properties to a minimum, and to
improve the suitable sintering temperature range.